Fluid-pressure brake.



W. V. TURNER.

FLUID PRESSURE BRAKE.

APPLICATION FILED'JUNE 25.1913.

1,177,668. Patented Apr. 4,1916.

WITNESSES INVENTOR MW WM UNITED sTATEs PATENT oEEIcE.

WALTER V. TURNER, OIE EDGEWOOD, PENNSYLVANIA, ASSIGNOR TO THE' WESTING- HOUSE AIR BRAKE COMPANY, 0F WILMERJJING, PENNSYLVANIA, A CORPORATION 0F PENNSYLVANIA.

Specification of Letters Patent.

FLUID-PRESSURE BRAKE.

Patented Apr. 4, 1916.

Original application iled September 20, 1911, Serial No. 650,483. Divided and this application filed .Tune

' 25, 1913. Serial No. 775,688.

To all whom t may concern:

Be it known that I, WALTER V. TURNER,

a citizen of the United States, residing at v predetermined degree and such a device is v satisfactory undery certain conditions, but

more particularly in connection with recent development in fluid pressure brakes, it is desirable to provide a valve device which is operative, not according to the rate of reduction in train pipe pressure but only when the train pipe pressure has been quantitatively reduced to a certain predetermined degree.

The principal object of my invention is to provide a fvalve device of the above character which is operative to effect a reduction in fluid pressure for initiating an emergency application, upon a predetermined reduction in tram pipe pressure.

Inthe accompanying drawings, Figureil is a central sectional view of a triple valve devicey with my improvement applied thereto, showing the parts in normal release position; and Fig. 2 a similar view, showing the parts in emergency application position.

While my invention is shown applied to a triple valve device of the ordinary type, so as tosimplify the description, it will be understood that its use is of special importance with certain types of modern fluid pressure brakes, such as that described in application Serial No. 650,483 hereinbefore referred to and alsowith electro-pneumatic brake ap- A paratus such as that described in my prior vie. of the type covered by Patent No.

917,194, granted April 6, 1909, in which a h1ghervdegree of pressure is obtained in the brake. cylinder in an emergency application than isobtained in a service application of the brakes.

rI he triple valve device may comprise a caslng 1 having the usual piston chamber 2 containing triple valve piston 3 and valve chamber 4 containing a main slide valve 5 and graduating valve 6 adapted to be operated by the piston 3 upon a reduction in pressure in the train pipe 7 to effect an appl1cation of the brakes. The quick action emergency valve mechanism of the triple valve device comprises a piston 8 for operating a quick action valve 9 and said piston carriles a valvel 10 adapted to control commumcation from a passage 11 leading to a supply pipe 12 to one side of the piston 8.

y According -to my improvement, a valve plston 13 controls communication from the tram pipe passage 14 to passage 15 which opens into the triple valve piston chamber 2. The valve piston is adapted to seat in opposite extreme positions, a lower seat 16 being provided for engagement with a seat ring 17 and an upper seat 18 being provided for the seat ring 19 of the valve piston. An atmospheric exhaust port 20 opens to the upper side of the valve piston and a spring 21 acts on the valve piston in opposition to train pipe pressure on the lower side of same. The spring 21 is adjusted to the presarea of the valve piston is subject to train y pipe pressure in the seated position, the valve piston is lifted from its seat, instantly exposing the full area thereof to train pipe pressure. on the valve piston then quickly and positively shifts the same to its upper lseat in which communication from the train pipe foo The sudden increase in pressure passage 14 to the triple valve piston passage 15 is opened and communication from the triple valve piston chamber to the atmospheric exhaust port `20 is closed. Fluid under pressure is noW free to flow from the train pipe to the triple valve piston in the usual manner. v v

Vhenever from leakage or other cause, the train pipe pressure falls belovv the pressure for which the valve piston is adjusted to operate, the spring 21 acts to shift the valve piston 13 to its lower seat, thus opening communication from the triple valve piston chamber to the exhaust port 20 so as to cause a sudden reduction in pressure on the triple valve pieten Band its consequent movement to emergency position. This movement also` causes communication to be cut olf from the train pipe, so that leakage from the triple valve to the train pipe is prevented.

It Will noW be apparent that by means of my improvement, the automatic valve device is shifted to emergency position upon a predetermined reduction in train pipe pressure and by reason of the seating of the valve piston in its opposite final positions, leakage is prevented and a positive and prompt movement of same to open communication from the train pipe to the automatic valve device is secured.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In a liuid pressure brake, the combination with a train pipe and a valve mechanism operated upon a'reduction in fluid pressure for effecting an emergency application of the brakes,l of a valve device normally subject to atmospheric pressure and operating upon a predetermined reduction in train pipe pressure for venting fluid from said valve mechanism to operate the same without venting fluid from the train pipe.

2. In a fluid pressure brake, the combination with a train pipe and a valve mechanism operated by a reduction inl fluid pressure for effecting an emergency application of the brakes, of a valve devicesubject to the opposing pressures of the train pipe and a spring having its resistance effective to balance a corresponding train pipe pressure and operating upon a predetermined reduction in train pipe pressure for Venting fluid from said valve mechanism to operate the same without venting fluid from the train pipe.

3. In a Huid pressure brake, the combination with a train pipe and a Valve mechanism operated upon a reduction in Huid pressure for effecting an lemergency application of the brakes, of' a valve device subject to the opposing pressures of the train pipe and a spring and adapted upon a predetermined reduction 1n train pipe pressure to seat and cut off communication from the train pipe to said valve mechanism and to also vent fluid solely from said valve mechanism to operate the same to effect an emergency application of the brakes.

l. In a fluid pressure brake, the combination with a train pipe and a valve mecha.- nism operated upon a reduction in fluid pressure for effecting an emergency application of the brakes, of a valve device subject to the opposing pressures of the train pipe and a spring and adapted upon a predetermined reduction in train pipe pressure to seat and cut off communication from the train pipe to said valve mechanism and to also vent fluid only from said valve mechanism to operate the same to effect an emergency application of the brakes, said valve device being operated upon a predetermined increase in train pipe pressure for opening said communication and for cutting off the venting of fluid from said valve mechanism.

5. In a fluid pressure brake, the combination with a train pipe and a valve mechanism normally subject to train pipe pressure and operated by a reduction in uid pressure for effecting an emergency application of the brakes, of a valve device subject to the opposing pressures of the train pipe and a spring for controlling communication from the train pipe to said valve mechanism and having one position for opening a Vent port for venting fluid solely from said valve mechanism to effect an emergency application of the brakes, in which the train pipe communication is closed and another position in' which the vent port is cut olf from said valve mechanism and the train pipe communication is opened. j l

6. In a fluid pressure brake, the combination with a train pipe and a valve mechanism normally subject to train pipe pressure and operated by a reduction in fluid pressure for effecting an Vemergency appli- Acation of the brakes, of a valve devicevsubject to the opposing pressures of the train pipe and a spring and operated upon-a predetermined increase in train pipe pressure for opening communication from the train pipe to said valve mechanism and upon a predetermined decrease in train pipe pressure for closing said communication and for opening avent port for venting fluid solely from said valve mechanism to operate the same to effect an emergency application of the brakes.

. 7. In a fluid pressure brake, the combination with a train pipe and a valve mechanism normally subject to train pipe pressure and operated by a reduction in fluid pressure for effecting an emergency application of the brakes, of a valve device subject to the opposing pressures of the train pipe and a spring and adapted to seat and expose a restricted area to train pipe. pressure, said valve device being operated upon a predetermined increase in train pipe pressure for opening and exposing an increased area thereof to train pipe pressure and also establishing communication from the train pipe to said valve mechanism.

8. In a fluid pressure brake, the combination with a train pipe and. a valve mechanism normally subjectl to train pipe pressure and operated by a reduction in fluid pressure for ei'ecting an emergency appllcation of the brakes, of a valve device subject to the opposing pressures of the train pipe and a spring and adapted to seat andexpose a restricted area to train pipe pressure, said valve device being operated upon a predetermined increase in train pipe pressure for opening and exposing the full area to train pipe pressure and also establishing communication from the train pipe to said lvalve mechanism, a predetermined reduction-in train pipe pressure being adapted to close the train pipe' communication and open a qvent port for venting fluid from said valve mechanism to operate the same.

9. In a fluid pressure brake, the combination With a train pipe and a valve mechanism subject to train pipe pressure and operated upon a reduction in fluid pressure for effecting an emergency application of the brakes, of a valve device subject to the opposing pressures of the train pipe and a spring and operated upon a predetermined reduction in train pipe pressure for venting fluid `:from'said valve mechanism, said valve device being adapted to finally seat and expose a restricted area to train pipe pressure and being operated upon a predetermined increase in train pipe pressure to lift from the seat and expose a larger area to train pipe pressure.

In testimony whereof I have hereunto'set my hand.

WALTER V. TURNER. Vitnesses:

A. M. CLEMENTS, S. W. KEEFER. 

